1. Field of the Invention
The present invention relates to an image pickup unit equipped with a small image pickup device as well as to a manufacturing method of the image pickup unit.
2. Description of the Related Art
Recently, photographic apparatuses equipped with a built-in image pickup unit including a solid-state image pickup device such as CCD have been widely used. Such photographic apparatus include photographic cameras and video cameras. Among apparatuses which acquire still images, moving images, and the like for various purposes using a photographic apparatus, for example, industrial electronic endoscopes and medical electronic endoscopes are widely used.
Medical endoscopes, in particular, allow surgeons to observe lesions by inserting an insertion portion deep into a body or carry out inspection and treatment in the body by using treatment instruments in conjunction as required. Medical electronic endoscopes are expected to be downsized as much as possible to alleviate patients' pain when a distal end portion of the insertion portion is inserted. The image pickup unit incorporated in the distal end portion of the electronic endoscopes thus downsized is expected to be downsized as well.
For example, Japanese Patent Application Laid-Open Publication No. 2005-109092 discloses an image pickup apparatus in which a solid-state image pickup device is packaged for downsizing. In order not to increase manufacturing processes, the image pickup apparatus is configured such that an objective lens is urged against the solid-state image pickup device by a compression coil spring with the apparatus kept thin instead of fixedly bonding the solid-state image pickup device and an objective lens.